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 * Software License Agreement (BSD License)
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 * Author: Eitan Marder-Eppstein
 *         David V. Lu!!
 *********************************************************************/
#ifndef _ASTAR_H
#define _ASTAR_H

#include <global_planner/planner_core.h>
#include <global_planner/expander.h>
#include <vector>
#include <algorithm>

namespace global_planner {
class Index {
    public:
        Index(int a, float b) {
            i = a;
            cost = b;
        }
        int i;
        float cost;
};

struct greater1 {
        bool operator()(const Index& a, const Index& b) const {
            return a.cost > b.cost;
        }
};

class AStarExpansion : public Expander {
    public:
        AStarExpansion(PotentialCalculator* p_calc, int nx, int ny);
        virtual ~AStarExpansion() {}
        bool calculatePotentials(unsigned char* costs, double start_x, double start_y, double end_x, double end_y, int cycles,
                                float* potential);
    private:
        void add(unsigned char* costs, float* potential, float prev_potential, int next_i, int end_x, int end_y);
        std::vector<Index> queue_;
};

} //end namespace global_planner
#endif

